Introduction to the scientific ideas of Professor Victor A. Ramos on the Proterozoic and Paleozoic geotectonic evolution of the Argentinean-Chilean Andes: origin, evolution, and alternatives

Through a brilliant and proliferous career of 60 years, Victor A. Ramos has discussed aspects concerning the evolution of the Andes' structure, their basement, associated magmatism, basin evolution, geotectonic context, seismicity, and gravimetry. Deep thrust ramps associated with Andean structuration were interpreted by Ramos as due to crustal inheritance, either associated with Triassic extensional structures related to Pangea breakup such as lithospheric structures associated with Paleozoic accretions against the southwestern margin of Gondwana (ancient Rio de la Plata craton) from Early Cambrian onwards. Thus, in conjunction with embryonic proposals of other groups, a series of proposed amalgamated continental blocks were defined that explained the development of Paleozoic sutures, magmatic and orogenic belts, associated with ancient oceanic subductions and continental collisions: The Early Cambrian Pampean collision, the re-accretion of the southern part of the Arequipa-Antofalla terrane (Arequipa microplate) and the Cuyania collision in late Ordovician times, the Late Devonian accretion of the Chilenia terrane, the accretion of the Mejillonia and Pichidangui terranes and the collision of Patagonia in late Carboniferous times. Early hypotheses have diversified through time in multiple lines of scientific research taken from several scientific groups all across the world. We discuss their development in fertile ulterior scientific fields, their growth, and eventual transformation. Victor Ramos' scientific career exemplifies more than half a century of scientific growth in the tectonic evolution knowledge of the Andes and all the South America in general, and the description of his scientific work exposes achievements and limitations to his models that have allowed the birth of new theories. The tectonic plate paradigm was a profound dislocation of scientific ideas concerning the evolution of the Earth's crust. In Argentina, as in many other regions, this change triggered a complete revision of classical local geology and its re-interpretation, in which Victor Ramos was a pioneer.